Centrifugal separator with replaceable discharge outlet bushings



July 14, 1970 L. E. GILREATH CENTRIFUGAL SEPARATOR WITH REPLACEABLE DISCHARGE OUTLET BUSHINGS Filed June 10. 1968 2 Sheets-Sheet 1 Lafayette E. Gi/reath INVENTOR BY Z ATTORNEY July 14,1970

CENTRIFUGAL SEPARATOR WITH REPLACEABLE DISCHARGE OUTLET BUSHINGS Filed June 10, 1968 L- E. GILREATH 2 Sheets-Sheet 2 F IG. 3

{ Lafayette E. Gl'lrecl th IN VE NTOR ATTORNEY United States Patent "ice 3,520,473 CENTRIFUGAL SEPARATOR WITH REPLACE- ABLE DISCHARGE OUTLET BUSHINGS Lafayette E. Gilreath, 7623 Arnim, Houston, Tex. 77017 Filed June 10, 1968, Ser. No. 744,280 Int. Cl. B04b 11/00 U.S. Cl. 233-47 4 Claims ABSTRACT OF THE DISCLOSURE A discharge bushing or nozzle arrangement for centrifugal apparatus in which centrifugally separated material is discharged generally radially through openings which move circumferentially with the rotating apparatus. The apparatus has discharge bushings or nozzles in the discharge openings which are disposed in angular relation to radii along which the separated material moves, so that the outer ends of the bushings are disposed in circumferentially offset relation to the inner ends of the bushings in a direction opposite to the direction of rotation of the apparatus, whereby the material is caused to move in a substantially straight path away from the outer ends of the bushings, to prevent the wear or cutting away of the trailing outer edge portions of the bushings which takes place when the axes of the bushings are positioned radially relative to the axis of rotation of the apparatus.

BACKGROUND OF THE INVENTION In the centrifugal separation of solids from liquids it is usual to provide centrifugal apparatus including a receptacle or barrel which is rotated at high speed about its longitudinal axis and which has discharge openings through which the separated solids are discharged along paths substantially radially of the axis of rotation of the barrel.

Apparatus of this kind is customarily supplied with bushings or nozzle in the discharge openings which are likewise disposed radially relative to the axis of rotation and due to the high speed of rotation of the apparatus the discharged material tends to be diverted from its radial direction of movement as it flows through and outwardly beyond the outer ends of the bushings, so that trailing end edge portions of the bushings are rapidly worn or cut away by the discharged material. Such cutting away of trailing end edge portions of the bushings takes lace more or less rapidly depending upon the nature of the solids which are separated and the speed of rotation of the apparatus and in the separation of some kinds of materials, such as those containing abrasive substances, this wear is so great that frequent replacement of the bushings becomes imperative. Attempts have been made to prolong the life of such bushings by making the same of various hard and wear resistant material, but such expedients have not proven to be completely satisfactory due to the greater cost of such materials, and the uncertainty of their wearing qualities.

The present invention has for an important object the provision of centrifugal separator apparatus of the type mentioned which is constructed to greatly prolong the life of the discharge bushings and to permit the ready replacement of the same without disassembling the equipment.

SUMMARY OF THE INVENTION Briefly described the invention comprises centrifugal apparatus of the type having a rotating tapered barrel in which an inner rotor is provided which is rotatable independently of the barrel and is formed with an external, spiral flight closely fitting the inner surface of the barrel 3,520,473 Patented July 14, 1970 and which serves to move material toward the discharge end of the barrel upon rotation of the barrel and rotor in the same direction at somewhat different speeds. Means is provided for introducing the material to be separated through the rotor into the barrel at the larger end of the barrel so that solids are separated therefrom and moved by the flight toward the smaller end of the barrel while the separated liquid is allowed to flow out of the barrel at the larger end thereof. The barrel is provided adjacent its smaller end with circumferentially spaced discharge openings and has discharge bushings removably mounted in the discharge openings whose axes are positioned at an angle to radii extending from the axis of rotation of the bgrrel such that the outer ends of the bushings are disp sed in circumferentially offset relation to the inner ends thereof in a direction opposite to the direction of rotation of the barrel, to cause the material being discharged to move along straight paths as the material flows out of the bushings, whereby the flow of material over the outer end edges of the bushings is reduced, thus greatly reducing the wear or cutting away of the bushings.

The bushings are inserted in the discharge openings of the barrel and are removably retained therein by a retaining ring formed in two parts releasably secured together to provide openings in alignment with the. openings of the barrel into which the bushings also extend. The bushings and retainer ring are designed for coaction to releasably hold the bushings and retainer ring in position on the barrel.

BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS FIG. 1 is a side elevational view, partly broken away and partly in cross-section, illustrating a preferred embodiment of the centrifugal separator of the invention;

FIG. 2 is a cross-sectional view, on a somewhat enlarged scale, taken along the line 2-2 of FIG. 1, looking in the direction indicated by the arrows; and

FIG. 3 is a fragmentary cross-sectional view, taken along the line 3-3 of FIG. 2, looking in the direction indicated by the arrows.

DETAILED DESCRIPTION OF A PARTICULAR EMBODIMENT OF THE INVENTION The invention is illustrated herein in connection with its application to a centrifugal separator of the general type, disclosed in applicants copending application Ser. No. 682,188, filed Nov. 13, 1967, now Pat. No. 3,430,850, having an outer tapered barrel 10, whose smaller end is closed by a cover or end plate 12, formed with a central, tubular extension 14, to provide a bearing shaft or hub for one end of the barrel, and whose larger end is closed by a cover or end plate 16, formed with a central tubular extension 18, whose outer reduced end portion 20 provides a bearing shaft for the other end of the barrel.

The shaft 14 is rotatably supported on a suitable bearing such as a pillow block 22, and the shaft 20 is similarly supported on a pillow block 24, the blocks being carried on a suitable support structure, not shown, in the usual manner, to support the apparatus for high speed rotation about its longitudinal axis.

A hollow rotor 26 is rotatably disposed in the barrel 10, which rotor may be of longitudinally tapering shape. or otherwise, and is provided with an external, spiral flight 28 whose external edge is closely fitted to the internal surface of the barrel to convey material longitudinally along the barrel upon relative rotation of the barrel and rotor.

The rotor has a shaft 30 at one end, extending through the extension '18 and provided with suitable bearings, now shown, inside of the extension, and is mounted at its other end on suitable bearing means, not shown, located within the barrel. By this arrangement the barrel and rotor are mounted for independent rotation relative to each other, the shaft 14 of the 'barrel being provided with a pulley 32, or the like, by which the barrel may be rotated from any suitable source of power, while the shaft 30 is similarly rotated by means, not shown, from the same or some other power source.

A pipe 34 is extended axially through the shaft 14 into the rotor 26 and the rotor is formed with one or more outlet openings, not shown, leading from the interior thereof into the barrel, whereby material to be treated may be introduced into the apparatus while it is rotating.

In centrifugal apparatus of this kind the barrel and rotor are customarily rotated at high speed, in the same direction, but at slightly different speeds, so that solid material in the barrel, separated by the centrifugal action will be moved by the flight 28 toward the smaller end of the barrel, while liquid from which the solids are separated may fiow toward the other end of the barrel from which it is discharged through suitable openings, not shown.

Adjacent its smaller end the barrel has a number of outlet openings 36 within which discharge bushings or nozzles 38 are disposed and through which the solids are discharged from the barrel.

As ordinarily constructed, in apparatus of this kind, the axes of the openings 36 are disposed radially relative to the axis of the barrel and due to the high speed of rotation of the apparatus and the velocity at which the solids are discharged, there is a tendency for the bushings to be worn away along trailing portions of the outer ends of the bushings, which results in rapid wear of the bushings, necessitating frequent replacement of the same. It is for the purpose of reducing the frequency of replacement of the bushing and making the same more easily replaceable that the present invention is particularly designed.

In the present illustration, the barrel 10 is provided adjacent its smaller end with an external ring or collar, generally designated 40, formed in two annular parts 42 and 44, shaped to form when assembled on the barrel, openings 46 disposed in axial alignment with the openings 36 of the barrel into which the bushings or nozzles 38 are extended.

The annular parts are shaped to be assembled about the exterior of the barrel, adjacent its smaller end, with the bushings 38 in place in the aligned openings 36 and 46 and releasably secured together as by means of bolts 50, whereby the parts will be securely held in assembled relation on the barrel, but may be readily detached therefrom for the purpose of replacing the bushings.

The bushings 36 are of tubular shape, formed of suitable material, which may be a hard, wear resistant material, such as hardened steel or other wear resistant material such as tungsten alloy or other suitable material. Each of the bushings may be formed with an external annular flange or projection 52 mediate its ends, which is positioned to be received in a counterbore 54 formed in the ring parts 42 and 44 at the inner end of each of the openings 46, and against which the outer surface of the barrel 10 bears, as seen at 56 in FIG. 2, to hold the bushings against axial movement when assembled on the barrel.

As indicated in FIG. 2, the axes of the openings 36 and 46 are disposed in angular relation to radii extending from the longitudinal axis of the barrel, so that the other ends of the bushings are positioned in somewhat circumferentially offset relation to the inner ends thereof in a direction away from the direction of rotation of the barrel. The angular tilting of the bushings thus provided may be to any desired degree, and in general will depend to some extent upon the nature of the material being discharged and the speed at which the apparatus is rotated.

In general it is desirable to position the bushings at such an angle that the material will be discharged in a substantially straight path through the bushings without changing its direction until the material has moved out of the bushings, so that the flow of material over the outer end edges of the bushings is reduced to a minimum, thus greatly reducing the wearing or cutting away of outer end portions of the bushings.

In practice the bushings may have their axes disposed at an angle of approximately ten degrees to a radius passing through a point on the axis of the bushing substantially midway of the length of the bushing. The angular relationship of the bushing to such radius may, however, be varied to best suit the material being discharged and the conditions of use of the equipment to obtain a straight path of flow through the bushing to avoid wear on the other end portion of the bushing caused by material flowing over the outer end edge thereof.

It will be apparent that by loosening the bolts 50, the annular ports 42 and 44 may be released from the bushings 38, to allow the bushings to be rotated about their axes to position substantially unworn trailing outer end edge portions of the bushings at locations to replace worn trailing outer edge portions thereof. Moreover, when the outer end edges of the bushings have become substantially worn throughout their circumferences, the bushings may be readily removed and replaced with the opposite ends outermost to replace the worn ends, thus greatly increasing the useful life of the bushings.

In the event that it should become necessary to replace the bushings, the parts 42 and 44 of the ring 40 may be disassembled by removing the bolts 50, whereupon the parts may be separated and the bushings removed from the openings 36 and replaced.

It will thus be seen that the invention, constructed as described above, provides centrifugal apparatus having discharge bushings which are readily replaced and which are positioned to obtain the maximum of wear before replacement.

It will readily be appreciated that the discharge bushing and arrangement of the invention may be used with equal advantage in connection with centrifugal separators of other types than that described herein which is intended by way of example only.

The invention is disclosed herein in connection with a particular embodiment of the same which is intended to be illustrative only, it being understood that various changes can be made in the construction and .arrangement of the parts, within the spirit of the invention and the scope of the appended claims.

Having thus clearly shown and described the invention, what is claimed as new and desired to secure by Letters Patent is:

1. In a centrifugal separator having a barrel mounted for rotation about its longitudinal axis to cause the separation of heavier from lighter material by movement of the heavier material along a path extending radially outwardly from said axis,

said barrel being formed with an outlet opening in its side wall,

a tubular bushing movably disposed in said outlet opening for rotational adjustment therein about its axis and whose outer end is offset circumferentially of the barrel from the inner end of the bushing in a direction opposite to the direction of rotation of the barrel,

ring means surrounding the barrel and having an opening into which said bushing is extended, said bushing, ring means and barrel being shaped for interengagement to releasably hold the bushing against rotational movement about its axis.

2. The centrifugal separator as claimed in claim 1, wherein said bushing is shaped to be removably positioned in said opening with either end of the bushing located outermost of the opening.

3. The centrifugal separator as claimed in claim 2,

wherein said bushing is formed with an external annular flange mediate its ends, and said ring means is formed with an enlarged radially inwardly opening counterbore at the inner end of the opening of the ring means whose bottom wall is positioned for coaetion with said flange and barrel to hold the bushing against radial movement 5 relative to the barrel.

4. The centrifugal separator as claimed in claim 3, wherein said ring means is formed in two annular parts and including means for releasably holding the parts in 10 assembled relation.

References Cited UNITED STATES PATENTS 2,578,456 12/1951 Smith 2337 3,108,952 10/1963 Antz 23346 X FOREIGN PATENTS 682,451 11/ 1952 Great Britain 233-46 ROBERT W. JENKINS, Primary Examiner 

